Method of evaporating aqueous solutions.



METHOD 0FV rEVAPORTING AQUEOUS SOLUTIONS'. i

APPLICATION FILED DEC-8.1913.

" Patented Apr. 3, y1917.

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` R. U. BUYNKER.

METHODv OF EVAPORATING AOUEOUS SOLUTIONS. APPucATmN 'man 050.8. 1913.

.41,221,022. l Patented Apr. 3', 1917.

annesse-$- Y R. U. BUNKEH. METHOD 0F EVAPORATING AQUEoUs soLuTlo is.

APPucATmN man fge. |913.,

Ptented Apr. '3, 1917.

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R. u. BUNKER.' `METHOD 0F 'EVAPURATINGWAQUEOUS SOLUTIONS. APPLICATION FILED yDIEC.B. 1913. v

4 SHEETS-#SHEET 4.

RAYMOND U. BUNKER, 0F YONKERS, NEW YORK.

METHOD OF EVAPORATING AQUEOUS SOLU IIONS.

Specification of Letters Patent.

Patenten Apr. 3, 1917.

Application led December 8, 1913. Serial No. B05 ,372.

To all whom it may concern:

Be it known that I, RAYMOND U. BUNKER, a citizen of the United States, residing at Yonkers, county of lVcstchester, and State `of New York, have invented certain new and useful Improvements in Methods of Evaporating Aqueous Solutions,of which the following is a clear, full, andl exact dei scription,j

Tlifs` invention relates to methods of evaporating aqueous solutions such as those of sugar, salt, etc., and more particularly to a multiple effect continuous graining pan.

` If on the principle of evaporation in multiple effect the concentration of sugar solutions, for instance, is carried beyond the point Where crystals develop, trouble is en countered. In such a case some of the crys talsare always left behind in each body or .chambcras the liqi advances through the apparatus. Those iystals which remain toolon'gin any one body or chamber grow unduly large, smear develops and a conglomeratemass results which, on being released to the atn'iospherc, resembles conf cretel VVh'enever a handsome uniform grain, termed lby the. trade granulatedA sugar, is desired the single effect or inter-- mittcnt vacuxun pan hasl been found neces.

sary.

. By means of the method forming the sub- ]e.ct of the present invention, uniform crys tais of suitable appearance and hardness may beproducedcontinuously 1n multiple effect, with consequent saving in heat and labor over the vpresent method of using single effect vacuum pans only. By the use of :thedescribed new method, clean crystals willbe produced and the final concentration" of all sugar solutions for instance, will be'cffectuated with thc same heat economy is fas effected in the well-.known multiple effect evaporator in? treatingy the solutions.

Another object of the invention is to pro.

vide practical and cfiicient means for grainrng sugar, salt, ctc..

-These being among the general objects of *the* invention, the saine consists of certain ste is in the method, to be `hereinafter descrlbel and then pointed Vout in the claims with reference to the accompanying draw- Y ings illustratnga suitable embodiment of i' an apparat-us for carrying outthe invention,

effect continuous graining pan, embodying the invention;

Fig. 2 is a plaii view of the same parts, showing in addit on a liquor supply tank;

Fig. 3 is'a side elevation of the cham- 60 bered body which is shown next to that at the left-hand end of Fig. 1;

Fig. 4 is a View partly in plan, and partlyi in section on the line 4-4 Fig. 3; a'nd Fig. 5 is an erlarged vertical section on 65 the line 5--5 Fig. 4, showing the interior of one of the bodes.

Referring to (he drawings, a plurality of chambered bodies 10, 11, 12 and 13 are shown; in the present instance, four. The general construction of these bodies is wellknown, but certain iml'irovemcnts have been added thereto by the present invention. Each of said clninbe'red bodies 10, 11, 12 and 13 is dividec 'in its lower portion into a number of pock ats, such as 14;, 14, 14";and 111, which are shown in connection with the chambered body l1. These pockets are indicated in broken lines in Fig. 2 but can be seen more-clearly in Fig. 4 from which it will be seen `that said pockets are separated by transverse upright walls 15. These walls extend from the .)ottom of each chambered body Vtoward the top of the same but are separated from tl c top by a transverse space 15 which is in tl e upper part of each body in common with all of the pockets therein. ln the lower pari of each pocket is a heaterV or calandria 16, so that each pocket has its own heater. These heaters may, when expedient, be constructed with Vtubes like. boiler. tubesso as to permit of the desired ebul'lition of the contents of' the pockets. For the purpose of withdrawing condensed vapors, the said heaters are provided with 95 discharge pipes L7, 18. The said pockets I may be said to c )rrespond with ay plurality of pans each having its separate heater and other accessories, and the said pans having a common vapor space comparable with the 100 V space 15a above mentioned. i

Having now Idescribed 'the general construction of the chamberedfbodies and the parts in them, tl te new arrangementI of the bodies will be explained. i In multiple effect 105 continuous evapo rators heretofore in use, the 'syrup or liquor i; advanced from ther chambered body of tie highest tempeature and lowest vacuum to the next following bodies ofl gradually derreasng ltemperatures and 11o increasing vacuums, or, permitting the vapors to take the same course as above, the iquor 1s passed through the apparatus in re- -verse direction. The plan of the present invention is to divide up the work of concentration approximately from 58 to 95 Brix `into a multiple number of stages. In general, four sta es would be convenient, as is the case in t e preliminary concentration, and consequently the four bodies before referred to are shown. Under the present invention the material to be concentrated, as

for instance massecuite, is advanced not step by step with the vapors, but to that body in which a suitable temperature offers to best carry on the next stage in graining or crystallization. Thus boil down in thecoolest body 10, in which the materialfto be concentrated may have a temperature of 135 F.

-and the body 23l of vacuum, this body 10 vacuum o 5; In the body 12 the grain is baked in at a high ltemperature tn prevent smean Lastly, transfer the material to be concentrated, as m'assecuite, to the chambered body .13 in which the material to be concentrated may be a temperature of 160 F., and said body a vacuum of 18".

For convenience in the transference of the Sugar solution and massecuite, the bodies 10, 11, 12 and 13 are lined up in the order of .progression of the sugars and suitable temperatures are arrived at'in any one body, not by bringing the vapors from the next body ad'acent but possibly from the second or thlrd distant body. The apparatus whereby this method of working may be carried out will now be further described. Each of the pockets of the chambered body 11 is provid,

ed, below the latter, with a connection 19, by means of which-a batch may be admitted into and dischar ed from the particular l pocket having sai connection. Eachof the other :bodies 11,` 12 and 13 have'corresponding'connections 19", 19" and 19, respectively.

Certain branches of each of said connections4 are connected with suitable charge pipes 21, 2 1, 21'and 21. which may lead from a sugar liquor tank 23. Means are'providedfor 'connecting the chargccpipes 21 andso -on withA anyarticular p etV of any one of the cham ered-bodies. To this end the charge pipes are connected with manifolds 22, 22,

by* valves 2Q, 203, 20" and 20 with the connections such as 19. l The valves 20, 20, 20" and 20 may be opened and closedby means of suitable` mechanisms, through the medium of hand-rotated shafts 45. It will therefore be s'een that the V,charges of sugar or other liquor to the pockets in the chambered bodies are so controlled bythe said valve mechanism that each pocket may be charged independently of any other pocket.

Between adjacent bodies 10, 11, 12 and 13 are located pumps 27 for the purpose of pumping the massecuite from body to body. To permit this, the saidy connections, such as 19 are adapted to discharge downwardly through foot-valves 24, and the connections 1)a through footvalves 24. The foot-valves 24, and all -valves corresponding therewith, are controlled separately by means of handrotated shafts, 46, andthe said Valves are connected to a manifold 47 for each body 10 and so on, which manifolds are in turn; connected with pipes, as 25, leading to the pumps, from which pipes 25'l lead. The pipes 25 lead to manifolds,l as 48, whic in turn are connected to the connections o the bodies 11, 12 and 13, by charging valves such as 26 for the second chambered body 11. It will therefore be understood that the chain.- bered bodies 10, 11, 1.2 and 13 are provided with corresponding charging valves such as 20 for independently controlling an inlet of sugarv liquor,l for instance, to each pocket such as 14; theyl are also provided with corresponding foot-valves such 4as 24 for controlling the discharge of massecuite, for instance, from Veach pocket independently; and the bodies 11, 12 and 13 are provided Awith corresponding charging valves such as 26 for controlling the inlet of massecuite independi ently into each of the pockets of saidbodies, from the body which is in advance.

A steam supply manifold 28 is by means of vapor valves 29 connected with the pockets of the chambered body 12 s o that the separate heaters of said pockets such as' 16 may be 'supplied' separately with steam.

The flow of the vapors fromthe chambered n body 12 and through the `vseriesof bodies. is as follows: From the body 12 to the body 11, through the medium of a vapor Pipe 30` Y n connected with a manifold 31, which is connected separately with the pockets in the y body 11 by means Vof vapor valves 32 'conjnected with the heaters in the separate pockets. vapors pass-by means of a vapor pipe to a manifold 35 which is, connected to the4 separate pockets of the -chamberedbody 13 by means of vapor valves 36', Finally the vapors ass fromzthe ch'ambered body 13 a` manifold 38 for thie first body 10, saidV 65 22band 22?- and the manifolds are connected manifold being connected by means of AFrom chambered body 11 thil 5 Athrough a vapor pipe 37 which leads over to `lowest vacuum, to the 13 and 10, of gradually decreasing tempera-` chambered bodies of the charging valves such .contents of that vaplor valves 15S) and pipes 40, within the poclictsof :the body 10, with the pocket heaters Vsuch as 16. Similar connections such as 4:0 lead the vapors to each heater of all of the bodies 10, l1, 12 and 13.

It will therefore be seen that the vapors from one (':hambered body to the next and so on pass in one sequence and that the massecuite, for instance, .may b e advanced from body to Abody in a different sequence, but not successively or in numerical sequence along the bodies as a liquid, as will now appear more clearly. The method is carried out as follows: In the first instance sugar liquor, for instance, is admitted to the series of pockets of each body 10, 11, 12 and` A13,the quantity being under control as those at 20. The advance of the massecuite through the series of chambcred bodies is, controlled (the valves such as at 20 being closed) by means of the pumps between the bodies and the valved connections before described. l t will be seen therefore that the massecuite may be advanced from the coolest body 10 to the next body 11 of most suitable te1nperature and vacuum; from the body 11 to the body 12 of the next most suitable temperature, and finally to'the body 13. The course ofthe vapors proceeds in a different series of steps, that is to say from the heater of body 12, of. highest temperature and heaters of bodies 11,

tures and gradually increasing vacuums.

As regards the pockets of the different and the utility of the same, the method of procedure Ais as fol-V lows: A complete transference of all growing crystals of like age inone batch may be effectuatcd .from body to body without disturbing the vacuum in any given body, and. this particularly desirable Where each body has pockets, as all the pockets in each body' have a common vapor space but sel'iarat-e heaters. By this means concentration' may be carried forward as far as is desirable in a given. pocket. Then the pocket may be lwithdrawn by a suitable regulation of the described valv'e mechanism and the pump (or by a barometric column) and introduced into the next body. The pocket thus left vacant may be thoroughly cleansed with hot water in Well known manner until all remainingr crystals are dissolved. The withdrawal above mentioned. may be accomplished without in any way disturbing' the c ontinuous operation of the apparatus as a whole. latchcs of massecuite may also be advanced from body to. body by means of the proper val-ves and the pockets and at the same time fresh charges-of liquor or syrup at or about 58 BriX may be introducedinto anyA body in order to promote the proper gro th of crystals, justas is done in any sing e effect pan. Eachy pocket should preferably have a well-known proofstick, such as-O, so that the matcqial heilig concentrated ma) be tested.

It is obvious that the ,invention is susceptible of a wide range of modification, as parts of the apparatus illustrated may be omitted, parts added and parts substituted without departing from the invention resident in the dcscri )ed method..

lVhat l claim au new is 1. The method of evaporating aqueous solutions in a serien of vacuum chambers of varying temperatl'res, which consists in'first boiling.,r down the material to be concentrated, as, for instance, massecuitein the coolest chamber, next boiling it. in a second rhamberat a high er temperature, then boiling it in a third chamber at still higher temperatore` fourth chamber, the said relation of'said chambers being oit of relation to the pro` gression of vapor i, and in which fourth chamber the temperature is lower than in the chamber prece( ing it.

2. The .method o." evaporating aqueous s0- lotions in a multiple effect continuous graining pan, which` consists ,in boiling down charges of the material to .be concentrated, for instance, massecuite, in the various cham# bers at different te mperatures, passing the vapors step by ste o through the series of chambers, and adv lncing the charge from one chambeliinto an other but `into that chambcil` which is at the temperature to which'the charge shouldbe subjected for further concentration depending upon the existing stage of its evaporation, through the chambers in such Waythat the last of said series .o chambers in the order of advance of the charge is in a' dilferent relation to the order rif-progression 'of the vapors.

The method of varying temperatur( :s and vacuums, which consists in first boiling' down the material' as for instance .masseto be concentrated,

cuite, in the coolest chamber, next, boiling it in a second chamb er at a higher tempera-4 ture and lower vacuum, then' boiling 1t ma,"

-of which is divided into a. number of pockets having a vapor space in' common, which consista in boiling the' material to' be concenand finally boiling it in a` said vapors being passed' evaporating aqueous sfo-V lutions 1n a series of vacuum chambers of4 trated, as for instance, massecuite, in sep-arate batches in said pockets, conveying to` gether the vapors passing oil' during ebullition, from the vapor space of one chamber to that of another chamber, and transferring the material to be concentrated as' frequently as desired from one or the other of said pockets in one chamber to one or the other of the pockets of another chamber when the concentration is carried forward still farther, whereby the vacuum in any chamber is not disturbed.

5. The method of evaporating aqueous solutions in a series of vacuum chambers, each of Which is divided into a number of pockets having a vapor space in common, which consists in charging any number of said pockets with liquor or syrup, then emptying a. pocket tents of the pockets not involved in suchI transfer.

Signed at New York city, New York this 3d day of December, 1913.

RAYMOND U. BUNKER.

Witnesses:

GEO. L. WHEELOCK, BEATRICE Mmvrs. 

